The invention relates to a heat exchanger with at least one connecting element. In addition, the invention relates to a process for the production of a connection between a heat exchanger and a connecting element.
A heat exchanger with stacked construction is known, for example, from DE 93 09 741. This heat exchanger comprises trough-shaped stacked blanks placed within one another, and also closing or end plates. The components are soldered to one another and in this way provide a system sealed to the external environment. Inlets and outlets are provided for the coolant circuit and for the circuit for the fluid to be cooled.
At least one of the end plates is constructed as a flange for attachment of the heat exchanger. This flange can be provided with bores and attached to the intended mounting location with the aid of, e.g., screws. However, this solution has the disadvantage of the additionally resulting work cycle for providing the bores in the end plates. A bore must also be provided on the mounting location, possibly with threads. The screws used as fasteners also require an additional expenditure for components.
The production of the heat exchanger typically occurs in an oven. The components of the heat exchanger coated with a soldering material are loosely preassembled and provisionally fixed. The oven is at a temperature at which the soldering material melts and flows into the joints of the individual components. In this way, the components are attached to one another, and the circuits are sealed in relation to one another and to the environment.
The object of the invention is to provide a combination of the heat exchanger and/or its connecting elements which is optimized in regard to manufacturing expense, mounting expense, and/or functional reliability.
This object is achieved by the invention as described and claimed hereinafter. Furthermore, processes for the production of the connection between the heat exchanger and its connecting elements and/or the mounting location also fulfill the objects of the invention.
The combination of heat exchanger and connecting element according to the invention has an attachment mechanism which comprises holding devices on the heat exchanger which work together with locating elements on the connecting elements. Additional attachment means, such as, for example, screws, are not necessary. The holding devices are constructed as part of the housing.
The holding device and the locating elements have a simple geometry. The locating elements can therefore be provided in the original mold of the connecting elements. Additional work cycles, for example for the provision of bores which cannot be provided in the original mold without undercuts, are therefore unnecessary.
One practical embodiment of the inventive concept envisions production of the holding device by deformation of specific parts of the heat exchanger, particularly the end plates. The end plates are generally stampings and are frequently provided with beads for stiffening. In these process steps, holding devices can also be formed in the end plate without additional manufacturing expense. Therefore, almost no additional costs arise due to the provision of these types of holding devices.
Another variant of the holding device comprises profiled strips which are permanently soldered to the housing. The profiled strips can be produced from economically obtainable, semimanufactured products. They can be integrated into the loosely premounted bundle of stacked blanks of the heat exchanger at insignificant additional expense. A permanent attachment results between the profiled strips and housing due to the treatment in the oven. The treatment of the heat exchanger in the oven is a production step which results due to the stacked blank assembly of the heat exchanger. Therefore, no additional process step for attachment of the holding device to the heat exchanger is necessary in this variant either.
It is advantageous to provide locking devices in the connection between the holding device on the housing and the locating elements on the connecting elements. These have the purpose of preventing undesired soldering of the connection. If the connecting elements are made of synthetic resin material, the intrinsic elasticity of this material can be used, for example through the provision of resilient snap hooks. Providing locking devices has the advantage that the connection between the connecting elements and the heat exchanger can be made detachable.
Of course, the holding device on the heat exchanger and the locating elements on the connecting elements must correspond with one another. For this purpose it is particularly necessary that the connecting element be provided with an appropriate geometric configuration. This can be achieved in accordance with the invention, for example, by providing grooves or flanges on the connecting element which engage the holding devices on the heat exchanger. If the connecting elements are, for example, oil filters with an essentially centrally symmetric geometry, these grooves and/or flanges can be produced without undercuts by a parting line which runs through the axis of symmetry.
A process according to claim 7 may be used for mounting the connecting elements on the heat exchanger. In this process, the connecting element is brought to the assembly point provided on the heat exchanger. Subsequently, the holding devices are plastically deformed, for example through bending. A positive interlock is hereby produced between the connecting element and the heat exchanger. The connecting element hereby remains largely undeformed.
The connection described between the heat exchanger and the connecting element is not detachable unless one brings the holding device back into its original shape. Nonetheless, the mounting process through deformation of the holding element is very economical, particularly for large piece counts. The mounting can be performed by machine in an apparatus provided for this purpose.
As an alternative to this, a mounting process is claimed in which the connection between the heat exchanger and the connecting elements is produced by a relative motion of these parts. This can, for example, be realized by a kind of bayonet lock. The connecting element is placed onto the heat exchanger and affixed to the heat exchanger with a rotation.
These and further characteristics of preferred embodiments of the invention can be seen both from the claims and from the description and the drawings, and the individual features of the invention can be realized alone or jointly in the form of sub-combinations in embodiments of the invention and in other fields, and represent advantageous embodiments protectable in and of themselves, for which protection is claimed here.